NCJ Number
126310
Date Published
1989
Length
13 pages
Annotation
Seven hundred and forty-seven college students (276 males and 471 females) were given a questionnaire containing two problem scenarios and were asked to make judgement concerning the probability of certain occurrences. The study was designed to measure the impact of confidence and data specificity on probability estimation, a key behavior in gambling decisionmaking.
Abstract
The scenarios concerned the amount of rainfall in Buenos Aires and the average number of points scored per game in a season by a basketball team. The experimental design was comprised of four manipulated variables and one classification independent variable with four dependent variables. The findings indicate that, in general, people are able to use all available data to estimate probability of an occurrence. Large standard deviations were accurately estimated while small ones were vastly overestimated; females gave probability distributions with greater variabilities than did males. As hypothesized, data with large variance led to lower confidence judgements than more specific data, however task complexity, as measured by list length, did not affect judgement confidence. The results suggest that people are more confident about judging situations where they feel knowledgeable, even if this belief is not justified. The implications of this study for gambling are that females should be more cautious when making decisions under risk or uncertainty, that males will feel overconfident about risky decisions, and that females will usually make smaller wagers. The perception of variance and its influence on judgement may explain the under/over bettor bias, while the relationship between variability and confidence may explain a preference for low variability gambling games. 3 tables and 19 references